Predators affect prey not only by directly killing them but also by modifying the behavior of prey individuals. Since the anti-predator behavior reduces the rate of encounters between predators and prey, the predator functional response declines with predator density. On the other hand, consumers that spend long time in avoiding predation risks have to sacrifice feeding efficiency and the consumer functional response also depends on predator density. We study indirect effects of these interaction modifications on stability of tritrophic food chains.